A man and his cat, nothing else. The show sits with that simplicity long enough that you stop waiting for a plot to arrive and just breathe with them instead. Leiji Matsumoto made this for a real animal he loved, and you can feel that restraint, no manufactured sentiment, no trying to make you cry. It exists because he needed to document a moment that mattered to him. You're not watching a story. You're allowed to be quiet in someone else's home.
Torajima no Miime is a two-episode special from 1999 that was released alongside the Queen Emeraldas OVA. It is a short slice-of-life story made as a tribute to Leiji Matsumoto's cherished cat, Mii-kun.